Fertile Floods: Croatia's Wetlands (2018) - full transcript
A picturesque region in the Balkans
packed with strange customs
birds eat with spoons
horses go bathing and a big
mouth go swimming in the woods
in the middle of Croatia there
is an abundance of water
the unpredictable waters of
the Sava know no restrictions
and create an amphibian world
flooded for months at a time the wetlands
are home to swarms of young creatures
like the ugly ducklings
piggyback chicks and builders
busy grooming themselves
in the floodplains large birds catch
fish and large fish catch bird
here people live with the water as was usual
in many parts of Europe centuries ago
at a time when rivers could meander
as they pleased
an ancient cultural landscape in which many
domesticated animals can wander freely all year round
like the deer in the forests
and the beavers in the water
that landscape shows us today
what flood protection can mean
[music]
the most plentiful tributary of the Danube
has its headwaters in the julian alps of Slovenia
fed from glaciers snow and ice one of its stems has
its source in the foothills of Mount Airy Bluff
this is where the Sava river begins its
over 940 kilometer journey
emerald-green Springs produce crystal-clear
groundwater like miniature volcanoes
before it got this far it trickled down
underground through the mountains
it's still winter up here
everything is sheathed in ice
even lake behind where the two stems of the
Sava join forces still has a coating of ice
from here the Sava continues as a tumbling mountain
torrent towards the Danube and the Black Sea
to save energy in this gushing River the trout
and speckled trout aim into the current
despite the bitter cold of the winter
many parts of the Sava remain ice-free
where he becomes shallower it freezes
over from the banks towards the center
but the fast flowing current will not permit
the ice to cover the surface completely
mountain streams like this are the preferred
hunting ground of a rather special bird
the white throated dipper relies on the streams
not freezing over completely in the winter
it doesn't just dip its head into the water
to hunt for amphipods or insect larvae
the Dipper is the only songbird that can
swim and can dive for up to 30 seconds
it even takes a dive into the gushing Sava
where a Danube salmon has already caught its
lunch but is having difficulty swallowing it
there was a time when this predatory fish that grows up to 1.8
metres in length was ubiquitous throughout the Danube area
today the Danube salmon is less frequent
it needs fast flowing well oxygenated
rivers with plenty of gravel to breed in
in many places those rivers have been
dammed with barges and lock systems
this is why the untamed Sava is a
crucial retreat for the Danube salmon
the Sava is still passing through
mountainous country but soon the
gradient becomes less obvious and the
river completely changes its character
as it passes through Slovenia Croatia
Bosnia Herzegovina and Serbia
the lively mountain stream from the
eastern Alps becomes a leisurely
meandering river that joins
the Danube at Belgrade
halfway along southeast of Zagreb it snakes through
flat plans with only the slightest gradient
here in plaza vena lies the
long scope olia nature reserves
in one of the last contiguous
River landscapes in Europe
in the cold winter many of the side arms of the
sava wetlands are frozen to a large extent
in the Balkans the summer is much warmer than in
Central Europe but the winter can be very hard
there are not many sections of this tranquil
stretch of water that stay free of ice
they're only superficially frozen and
many of the fish spend the winter here
as do the great white heron they may look exotic but
they can deal with extremely frosty temperatures
since they don't only live off fish they don't
have to migrate when the waters freeze over
they find enough mice and other
small animals under the snow
and this fox is hoping his luck ease in today
the open sections of the Sava are
a center of attraction for many
mute swans the largest waterfowl in
Europe get social during the winter
sometimes dozens of them will congregate
around the unfrozen arms of the river
in places like this no movement in the water
will go unnoticed by the white and grey herons
after all it might be a fish and in these
temperatures every calorie is precious
and worth an argument
and this wild boar does not want to be left out
so he goes over to sort the herons out
and disappears into the extensive
forests of the Sava wetlands
the Nature Reserve is not only
home to centuries-old Slavonia oak
whose particularly durable wood is highly
sought-after for furniture and wine barrels
it's also where the best ham is
domiciled so the saying goes
the winter resistant Europe olia pigs with
their layer of fat up to 15 centimetres thick
live here all year round and root
around in the woods looking for acorns
during the Balkan war at the beginning of the 1990s
this ancient species of animal was nearly made extinct
but the robust original Europe aalia's are an
essential source of genetic material for pig breeding
fortunately it was possible to save them
and with them the traditional
grassland farming by the sava
an ancient cultural bio diverse landscape
artificial canals cut their
way through the wetlands
but the neatly felled trees
were not the work of humans
fresh tracks indicate that they're
still active even in the cold season
beavers do not hibernate these large
rodents have to eat regularly
they've stocked their underwater
ladders for difficult times
but wherever possible they prefer to
save their energy and eat fresh bark
even if the way to the next
snack is a little slippery
even the Magpies cantake a slide
now that it's slowly beginning to thaw some
small tip bits are becoming accessible
the great bitten likes to stalk along the edge of the reeds where
there are often breaks in the ice looking for unmoving fish
while Magpies as omnivores can survive in the
cold season by feeding on vegetarian meals
the great bitten needs its meat licious
then spring comes and in the julian alps where
the Sava has its source everything is thawing
water from the massive catchment
area tumbles over the cliffs
one great torrent is making its way
in the plaza vena plain the water masses build
up the entire Sava basin fills up sometimes as
much as 10 metres above the normal level
although it looks like a natural disaster this is actually
saving the towns along the Sava from urban flooding
the Sava wetlands act as a detention basin over
600 square kilometres is flooded every year
like an enormous sponge the alluvial forests soak
up the water from around 10 billion bathtubs
in the past many River landscapes
around Europe looked like this
these trees often spend several weeks
and months standing in the water
without these floodplains towns like Zagreb
and Belgrade would frequently be washed out
many animals benefit from the flooding
no less than 15 species of
amphibians like the moor frog
these 7 centimeter long frogs leave their
winter quarters on mass in the spring
and for the spawning season the
male's take on a blue color
these flooded meadows provide plenty of food
herons fish while beside them
the wild boar graze on
fresh greens in the water
or dig in the soggy soil for
insect larvae and roots
even the torah' polio
pigs wade in the marsh
with their powerful snouts
they plow the river landscape
they're digging action breaks up the heavy soil allowing
fresh grass to establish itself in the nutrient-rich mud
by maintaining this traditional
meadow management system
the inhabitants of the Sava region have found a way of
making the most of the wetlands despite regular flooding
they live with the water rather
than fighting against it
since the level can rise by 10 metres
overnight the houses are built on embankment
and usually 2 storeys high when the floods
come the inhabitants move up to the top floods
the Chi got village has 70 timber houses
and used to be home to 300 people there
are now only a hundred and twenty
but they have sub-tenants there are over
40 pairs of storks nesting on the roofs
g-gosh was christened Europe's first stork village
the inhabitants support the storks and provide
platforms for them to build their nests on
the alluvial forests are a plentiful
source of nest building materials
a stork's nest can have a diameter of 2 meters
many are the work of successive stork generations
when the partner returns carrying building materials
he or she is greeted with bill clattering
the nest is also the mating location
a balancing act high up on the roof
while the storks actively seek human
habitations to build their nests
others prefer the privacy of the alluvial forest
after the winter the mute swans
give up their social gatherings
they're strict vegetarians and
mainly live off aquatic vegetation
but when a pair start
exchanging aquatic undergrowth
they're collecting building materials
branches and twigs form the base construction
the greenery is for the padding
the swan couples like to build
their nests that are big enough for five
to seven eggs on small islands away from
the banks to prevent the Foxes getting close
the crested grebe have already laid their eggs in the
floating nest made of reeds branches and water plants
as underwater hunters they catch small fish
interspersed with aquatic insects and crayfish
this one has caught a
particularly bulky specimen
swallowing this large crayfish with its hard
shell and cumbersome pincers is quite a feat
once dinner is over the grebe
has to preen itself thoroughly
what looks like a heap of old sticks dumped in the
forest is in fact an architectural masterpiece
beavers build dams to
maintain a steady water level
the entrance to their Lodge is under
water to keep out land-based predators
they may not look very graceful a beaver
can weigh up to 40 kilograms which is
heavier than a roe deer but underwater
they cut a very streamlined figure
they propel themselves forwards with their
hind feet the scaly tail acts as a rudder
the beaver will gnaw at a large tree for
several days
once the tree has been felled that will
gorge themselves on the juicy leaves and
buds from the crown of the tree
thinner twigs up to the thickness of a pencil that's still
very soft are eaten completely with the wood and bark
many of the felled trees will
sprout again the next year
the larger branches are only used as
building materials for the lodge and Dam
this is what causes beaver Lakes
with constant water levels
these permanent water features created by beavers
are extremely important for the plants and
animals in the alluvial forests
the European pond turtle for example one of
12 reptile species in the Nature Reserve
these turtles prefer thick underwater
vegetation with muddy sediment
they usually mate in the water on dry
land it can be a risky affair
in summer beavers will mainly
eat juicy green vegetation
fresh herbs and foliage
buds and water lily roots
they generally only live off tree bark
in the winter when there's nothing else
a fully grown beaver needs a kilogram
of fresh vegetable matter every day
when they dive they can stay
underwater for a quarter of an hour
their nose and ears are closed off they can see because
their eyes are protected by an additional transparent skin
the lodge has now seen
the arrival of the kids
between April and June the female will give birth
to one to four kids with hair and their eyes open
the young spend the first month in
the living quarters of the lodge
for six to eight weeks they're subtle by the mother
as long as the kids are in the lodge they're safe
but out in the waters of the sava
terrifying predators are waiting
catfish can grow to 100 1/2 meters long
and weigh more than 50 kilograms
some have even been known to grow to three
metres in length and reach weights of
over a hundred and fifty kilogram
the sava wetlands are home to one of the
largest catfish populations in Europe
they're usually loners
but in spring there are
sometimes unusual gatherings
the focus is usually a group of overweight
females with swollen bellies full of spawn
a large female can lay up
to half a million tiny eggs
and yet these whirling catfish are not mating this
puzzling spectacle is perhaps a kind of foreplay
the mating act takes place only between
two catfish in private after the male
has created a spawning burrow in the
shallow water close to the bank
among thick underwater vegetation
there are many suitable places along the
sava the quiet side arms are often
overgrown with a thick mat
of pond and water lilies
they're juicy branches are nourishing
tidbits for the Beavers
and the broad floating leaves are a welcome
diving board for France hunting insects
in this way the Fertile waters of the wetlands are a
good source of food for many species and a nursery
one of the most common fish in the
Sava is not even from this area
in the densely vegetated shoreline pumpkinseed fish with
their black mark on the gill cover have found a hole
at the end of the 19th century the fish was
introduced in Europe from North America
and escaped from some garden ponds since it
breeds several times a year it was able to spread
rapidly across the continent
the pumpkinseed protects its
spawning burrows aggressively
it will even attack very large intruders
one level higher another baby has
just freed itself of its eggshell
stripe iya squeakers or baby boars its
siblings already swimming around the nest
the chicks of the crested grebe do not all
hatch out at the same time but a day apart
surprisingly the parents offer
their babies freshly pulled feathers
even order the chicks eat them
one explanation might be this it's
possible that the feathers protect the
tender stomach linings of the babies
against sharp fish bones
the first weeks the chicks spend a lot
of time in a cozy hollow of warm down
this protects them against the cold
water and the hot Sun
frequently the parents will go swimming
with the chicks on their banks
and they have even been known to dive with
but this grebe is just looking for a
more comfortable position on the nest
in their piggy back position the chicks are relatively
safe from predators in the air and in the water
the sava wetlands offer many different
possibilities for undisturbed nesting
some build floating nests where
they can bring up their young
another crested species the hoop hole find safe
breeding in tree hollows in the oak forests
here the young wait for their parents who take turns to
bring food mainly crickets beetles and larger caterpillars
in the alluvial forests the penduline tit hangs its nest from
a branch to build the nest it uses fine vegetable fibers
sometimes even spider's webs
the soft pouches used to be collected
for use as children's slippers
the who posed nest is now
attracting unwanted attention
there are strange noises in the hollow
a Starling is intent on stealing nesting material
and the Hoopoe keeps well out of the way
discretion is the better part of valor
but what does the Starling really want it
flies off without the nesting material
so the Hooper parents can carry
on with feeding their young in peace
two-thirds of the landscape olio Nature
Reserve is covered with alluvial forests
one third is wet meadowland which provides the
storks with a well-stocked larder to choose from
every adults talk requires a pound of food a
day and the chicks need more than twice that
so store parents have to transport
several kilograms of food every day
they poke around in the grass to find insects
and mice amphibians slugs and earthworms
if the meadows are under water they
catch crayfish and small fish their
stalks are characteristic of the Nature Reserve
there are over 700 pairs breeding here
they're constantly
repairing their nests this means they
can grow over the years to 4 metres in
height and can weigh up to 600 kilograms
after over a month of incubation the
young storks have hatched
at the beginning one of the parents will
always stay with the nest provide shade and
regurgitate tidbits for the clamoring babies
everywhere in the wetlands
there are newborn babies
after a good five weeks of incubation
the mute swan cygnets have hatched
in their grayish white plumage
they're anything but ugly ducklings
they preen themselves in the water
hands together with their parents in the nest
the swans distribute oil from their
preen gland all over their plumage
to make every single feather waterproof
soon after hatching the cygnets are expected
to find their own food in the water
the parents were there longer necks may
be able to reach deeper into the water
but that doesn't mean they're going
to give away any of their lunch
the wetlands are fertile along the banks of
the snaking Sava river there are cormorants
the water is teeming with fish
the larger catfish have retreated to quieter regions
the younger catfish are swarming
in the open water like tadpoles
catching amphipods and insect larvae
this way they confuse fish predators that
have to be able to concentrate on one target
there are predators hiding
everywhere in the wetlands
like this spotted eagle
that's just grabbing a pumpkin seed fish
the noisy cormorant colony where the birds brood
together high in the trees can be heard from a distance
the older fledglings extract their lunches
from deep inside their parents throat pouch
if it's very hot the parents also give them water
the diverse bird life in the
wetlands can't be taken for granted
the fine balance can easily be disturbed
this can be seen from the
crappier doll side arm
where grey heron and
spoonbills breed side by side
the heron are frequently seen in
Europe and even nest in large towns
the more rare spoonbills however
only frequent intact wetlands
at the end of the 1980s this sidearm was
drained and the spoonbills disappeared
fortunately there are now 120 pairs
here reading beside the herons
after the sidearm was returned to its natural
state the spoonbills returned within two years
and are now bringing up their
young again in this joint colony
and even the young have a spoon shaped bill
today attends of all the spoonbills in
Europe breed in crappy Adal
this is why the bird with the strange shaped beak
was honored as the symbol of the Nature Reserve
in the slit of the sidearm there are
other birds with odd-looking beaks
the Bill of the pied Avocet
bends upwards towards the tip
while the spoon bill uses its extremely
sensitive bill to search the riverbed
for aquatic insects crayfish and clams
the Avocet sifts for small
animals in the shallow silt
even the young chicks emulate this
my swing their heads to detect prey
since their tools dictate the way
they search and what they find
they do not infringe on each other's
territory in the crocodile sidearms
we're into midsummer in the wetlands
and the entire beaver family
has taken to the water
the youngsters are still a little
apprehensive about the water
and have to be encouraged to swim or are
even carried by the bank an adult and a
juvenile from last year are combing
their fur using the special combing claw
on their hind feet and applying oil to
making waterproof
they tend to spend several hours a day in the
water on average and can't afford to catch cold
on average the sava wetlands are flooded
for 32 a hundred days a year
it's not only in spring but in any month of the year
that powerful rainfall can cause it to burst its banks
and generate fertile habitats for many creatures
including the Osprey although it only weighs one other
half kilos is able to catch fish weighing two kilograms
after locating them with its eagle eyes from afar
and picking them out of the water
in the sava wetlands with their
plentiful supplies of fish the Eagles also have
ideal locations for their IRA's in the tall trees
normally they produce two to three chicks
these youngsters are already a few weeks old
allowing both the parents
to leave the nest regularly
to bring home enough food
for the family
the labyrinthine waters of the wetlands
are often murky so not all the fish
hunters need to have such good eyes as
the Eagles that hum from high in the sky
the large catfish have relatively poor
eyesight but their whole body and in
particular their long feelers is
covered with sensitive sense organs
this allows them to notice quickly in
the muddy sediment of the sidearms
if a competitor has already
staked out a good hunting ground
with their large mouths catfish can
catch not only fish and crayfish
their hearing is so sensitive that they can detect vibrations
outside the water and go to check out the hunting options
in the flooded alluvial forests the catfish
is looking for a particular hunting ground
there are reports of small dogs ending
up inside the jaws of the catfish
this is where pigeons come
down to the water to drink
they're flapping wings are a giveaway
that attacked was a failure
the pigeons are wary and don't allow themselves
to be dragged into the water that easily
they're still thirsty though and come back
a new opportunity for the catfish
the pigeons are forewarned
for they keep coming back
the third attack is a success
in the summer The Meadows are a blaze of red
a sea of poppies growing in
a field near the village
in agriculture in the Sava wetlands
the emphasis is on livestock breeding
but in some places arable
farming is also possible
peppers and sweet corn cobs
dry outside the houses
as they have done for hundreds of years
there's twittering coming from the
rafters Housemartins
in the protected environment of old
houses we find a whole colony
some of the Housemartins have
been here twice this summer
the others still have
to complete their nests
they build the walls of their nests
from inside using moist lumps of earth
until there is only their front door left open
there's a plethora of building
materials in the Sarver wetlands
thanks to the moist surroundings these Martens can
always find lumps beside puddles and on the banks of the
waters even in the hottest summer
it takes around a fourth life to build a nest
and then they lay up to five eggs in it
and up in the loft there's
a lively commotion
the mouse eared bats spend the
daylight hours up here squeaking
most of these are females and they will give
birth to their young here and bring them up
hundreds sometimes even thousands
of bats vie for the best places
holding on tight with their claws
they spend the day hanging upside
down under the wooden roof
there will swarm out after darkness
falls and go searching for food
thanks to their large ears they can locate
their prey in the dark by ultrasound
mainly all manner of insects
in these moist weapons there are many
different midges and flies moths and beetles
the floodplains of the sava are of importance
to the protection of birds throughout Europe
on the one hand they're the breeding area for
over a hundred and forty different bird species
numerous waterfowl like the snipe nest
in these moist meadows
but for migrating birds to the sava wetlands are one
of the most important rest areas on the continent
here they can plan a stopover to
recover from their long flights
and eat to their heart's content
all-in-all no less than 240 bird species
have been registered in the Nature Reserve
including the curl you
where the syrup olia pigs plow up the
sava mud in spring we now get fresh grass
a great benefit to the
powerful paws of inna horses
with their broad hooves they have no
difficulty walking over the soften ground
in the summer they like to enjoy
a cooling bath in the sava
since the start of spring the horses have lived
here without any human influence in the wetlands
with their fluctuating water levels
this is the ideal environment
for grass snakes
that can hunt mainly toads and
amphibians in the moist surroundings
the snake could hardly catch
healthy fish in the river
but when the water recedes from the
flooded Meadows the fish left behind in
the puddles virtually leaps straight
into the grass snakes mouth
this easy to catch prey also attracts stalks
onto the moist meadows and pasture land
they pick the juiciest insects
often they will follow the cattle on horses because as they move
around grazing they dislodge grasshoppers and other creatures
the storks benefit from these free roaming
domesticated animals in many ways
if there were no horses or cattle
here there will be fewer storks
on the one hand puddles of this
kind are maintained by them
because horses and other livestock wallow
in them and keep the muddy areas open
the sava wetlands though a considerable degree of their
diversity to the hungry stomachs of these large herbivores
without the help of these
natural mowing machines
the damp pastures would soon
degenerate into closed oak forests
this traditional pasture farming keeps
the ancient cultural landscape alive
and encourages Himura files like the stork to
breed here in large numbers
by the end of the summer there are more
storks living in g-gosh than people
in many nests for chicks are
produced sometimes even 6
when it's really hot the parents will dribble water
from their beaks into those of the chicks
and eating grass snakes find their
way from the swamp to the nest
and from there into a storks stomach
in the late summer early morning miss
rise over the Nature Reserve
a melancholy idle
when the sava wetlands of Croatia remind us
of paintings by famous landscape artists
and that is no coincidence because large
regions of Europe used to look like this
before the rivers were forced to behave
and flooding was normal
times when all over the continent riparian
wetlands could only be used naturally for grazing
this created landscape diversity has
still seen in the landscape olia puddles
and pools on moist meadows
mocchi sidearms and river meanders
traditional woodland and pasture
while the paws Avena horses spend their winter in
their stables the pigs stay outside all year round
in the autumn they're driven into the
woods where they mainly eat acorns
these woodland pastures keep the
forests open and free of undergrowth
and that produces park-like landscapes in the wetlands
when autumn arrives there's a
lot of action to see and here
during the last warm days of the year the squirrels
and foxes build up their layers of winter fat
and in the country by the sava
the Red Deer are heard bellowing
those from the posavina region are
some of the strongest in Europe
the most important time of the year is
fast approaching the rutting season
attracted by the bellowing of the stags the
Hinds gather at the traditional meeting points
these are usually spaces
that have not grown over
the Stags need open spaces to give
them room to impress the Highlands
and intimidate their rivals
the last big wetland area in Europe
is still a coherent mix of river and
flooding managed pasture and diverse nature
it's like looking into the past of our continent
that shows us how natural flood protection
for large towns and cities can be
as in the sava wetlands of Croatia
[music]
[music]
packed with strange customs
birds eat with spoons
horses go bathing and a big
mouth go swimming in the woods
in the middle of Croatia there
is an abundance of water
the unpredictable waters of
the Sava know no restrictions
and create an amphibian world
flooded for months at a time the wetlands
are home to swarms of young creatures
like the ugly ducklings
piggyback chicks and builders
busy grooming themselves
in the floodplains large birds catch
fish and large fish catch bird
here people live with the water as was usual
in many parts of Europe centuries ago
at a time when rivers could meander
as they pleased
an ancient cultural landscape in which many
domesticated animals can wander freely all year round
like the deer in the forests
and the beavers in the water
that landscape shows us today
what flood protection can mean
[music]
the most plentiful tributary of the Danube
has its headwaters in the julian alps of Slovenia
fed from glaciers snow and ice one of its stems has
its source in the foothills of Mount Airy Bluff
this is where the Sava river begins its
over 940 kilometer journey
emerald-green Springs produce crystal-clear
groundwater like miniature volcanoes
before it got this far it trickled down
underground through the mountains
it's still winter up here
everything is sheathed in ice
even lake behind where the two stems of the
Sava join forces still has a coating of ice
from here the Sava continues as a tumbling mountain
torrent towards the Danube and the Black Sea
to save energy in this gushing River the trout
and speckled trout aim into the current
despite the bitter cold of the winter
many parts of the Sava remain ice-free
where he becomes shallower it freezes
over from the banks towards the center
but the fast flowing current will not permit
the ice to cover the surface completely
mountain streams like this are the preferred
hunting ground of a rather special bird
the white throated dipper relies on the streams
not freezing over completely in the winter
it doesn't just dip its head into the water
to hunt for amphipods or insect larvae
the Dipper is the only songbird that can
swim and can dive for up to 30 seconds
it even takes a dive into the gushing Sava
where a Danube salmon has already caught its
lunch but is having difficulty swallowing it
there was a time when this predatory fish that grows up to 1.8
metres in length was ubiquitous throughout the Danube area
today the Danube salmon is less frequent
it needs fast flowing well oxygenated
rivers with plenty of gravel to breed in
in many places those rivers have been
dammed with barges and lock systems
this is why the untamed Sava is a
crucial retreat for the Danube salmon
the Sava is still passing through
mountainous country but soon the
gradient becomes less obvious and the
river completely changes its character
as it passes through Slovenia Croatia
Bosnia Herzegovina and Serbia
the lively mountain stream from the
eastern Alps becomes a leisurely
meandering river that joins
the Danube at Belgrade
halfway along southeast of Zagreb it snakes through
flat plans with only the slightest gradient
here in plaza vena lies the
long scope olia nature reserves
in one of the last contiguous
River landscapes in Europe
in the cold winter many of the side arms of the
sava wetlands are frozen to a large extent
in the Balkans the summer is much warmer than in
Central Europe but the winter can be very hard
there are not many sections of this tranquil
stretch of water that stay free of ice
they're only superficially frozen and
many of the fish spend the winter here
as do the great white heron they may look exotic but
they can deal with extremely frosty temperatures
since they don't only live off fish they don't
have to migrate when the waters freeze over
they find enough mice and other
small animals under the snow
and this fox is hoping his luck ease in today
the open sections of the Sava are
a center of attraction for many
mute swans the largest waterfowl in
Europe get social during the winter
sometimes dozens of them will congregate
around the unfrozen arms of the river
in places like this no movement in the water
will go unnoticed by the white and grey herons
after all it might be a fish and in these
temperatures every calorie is precious
and worth an argument
and this wild boar does not want to be left out
so he goes over to sort the herons out
and disappears into the extensive
forests of the Sava wetlands
the Nature Reserve is not only
home to centuries-old Slavonia oak
whose particularly durable wood is highly
sought-after for furniture and wine barrels
it's also where the best ham is
domiciled so the saying goes
the winter resistant Europe olia pigs with
their layer of fat up to 15 centimetres thick
live here all year round and root
around in the woods looking for acorns
during the Balkan war at the beginning of the 1990s
this ancient species of animal was nearly made extinct
but the robust original Europe aalia's are an
essential source of genetic material for pig breeding
fortunately it was possible to save them
and with them the traditional
grassland farming by the sava
an ancient cultural bio diverse landscape
artificial canals cut their
way through the wetlands
but the neatly felled trees
were not the work of humans
fresh tracks indicate that they're
still active even in the cold season
beavers do not hibernate these large
rodents have to eat regularly
they've stocked their underwater
ladders for difficult times
but wherever possible they prefer to
save their energy and eat fresh bark
even if the way to the next
snack is a little slippery
even the Magpies cantake a slide
now that it's slowly beginning to thaw some
small tip bits are becoming accessible
the great bitten likes to stalk along the edge of the reeds where
there are often breaks in the ice looking for unmoving fish
while Magpies as omnivores can survive in the
cold season by feeding on vegetarian meals
the great bitten needs its meat licious
then spring comes and in the julian alps where
the Sava has its source everything is thawing
water from the massive catchment
area tumbles over the cliffs
one great torrent is making its way
in the plaza vena plain the water masses build
up the entire Sava basin fills up sometimes as
much as 10 metres above the normal level
although it looks like a natural disaster this is actually
saving the towns along the Sava from urban flooding
the Sava wetlands act as a detention basin over
600 square kilometres is flooded every year
like an enormous sponge the alluvial forests soak
up the water from around 10 billion bathtubs
in the past many River landscapes
around Europe looked like this
these trees often spend several weeks
and months standing in the water
without these floodplains towns like Zagreb
and Belgrade would frequently be washed out
many animals benefit from the flooding
no less than 15 species of
amphibians like the moor frog
these 7 centimeter long frogs leave their
winter quarters on mass in the spring
and for the spawning season the
male's take on a blue color
these flooded meadows provide plenty of food
herons fish while beside them
the wild boar graze on
fresh greens in the water
or dig in the soggy soil for
insect larvae and roots
even the torah' polio
pigs wade in the marsh
with their powerful snouts
they plow the river landscape
they're digging action breaks up the heavy soil allowing
fresh grass to establish itself in the nutrient-rich mud
by maintaining this traditional
meadow management system
the inhabitants of the Sava region have found a way of
making the most of the wetlands despite regular flooding
they live with the water rather
than fighting against it
since the level can rise by 10 metres
overnight the houses are built on embankment
and usually 2 storeys high when the floods
come the inhabitants move up to the top floods
the Chi got village has 70 timber houses
and used to be home to 300 people there
are now only a hundred and twenty
but they have sub-tenants there are over
40 pairs of storks nesting on the roofs
g-gosh was christened Europe's first stork village
the inhabitants support the storks and provide
platforms for them to build their nests on
the alluvial forests are a plentiful
source of nest building materials
a stork's nest can have a diameter of 2 meters
many are the work of successive stork generations
when the partner returns carrying building materials
he or she is greeted with bill clattering
the nest is also the mating location
a balancing act high up on the roof
while the storks actively seek human
habitations to build their nests
others prefer the privacy of the alluvial forest
after the winter the mute swans
give up their social gatherings
they're strict vegetarians and
mainly live off aquatic vegetation
but when a pair start
exchanging aquatic undergrowth
they're collecting building materials
branches and twigs form the base construction
the greenery is for the padding
the swan couples like to build
their nests that are big enough for five
to seven eggs on small islands away from
the banks to prevent the Foxes getting close
the crested grebe have already laid their eggs in the
floating nest made of reeds branches and water plants
as underwater hunters they catch small fish
interspersed with aquatic insects and crayfish
this one has caught a
particularly bulky specimen
swallowing this large crayfish with its hard
shell and cumbersome pincers is quite a feat
once dinner is over the grebe
has to preen itself thoroughly
what looks like a heap of old sticks dumped in the
forest is in fact an architectural masterpiece
beavers build dams to
maintain a steady water level
the entrance to their Lodge is under
water to keep out land-based predators
they may not look very graceful a beaver
can weigh up to 40 kilograms which is
heavier than a roe deer but underwater
they cut a very streamlined figure
they propel themselves forwards with their
hind feet the scaly tail acts as a rudder
the beaver will gnaw at a large tree for
several days
once the tree has been felled that will
gorge themselves on the juicy leaves and
buds from the crown of the tree
thinner twigs up to the thickness of a pencil that's still
very soft are eaten completely with the wood and bark
many of the felled trees will
sprout again the next year
the larger branches are only used as
building materials for the lodge and Dam
this is what causes beaver Lakes
with constant water levels
these permanent water features created by beavers
are extremely important for the plants and
animals in the alluvial forests
the European pond turtle for example one of
12 reptile species in the Nature Reserve
these turtles prefer thick underwater
vegetation with muddy sediment
they usually mate in the water on dry
land it can be a risky affair
in summer beavers will mainly
eat juicy green vegetation
fresh herbs and foliage
buds and water lily roots
they generally only live off tree bark
in the winter when there's nothing else
a fully grown beaver needs a kilogram
of fresh vegetable matter every day
when they dive they can stay
underwater for a quarter of an hour
their nose and ears are closed off they can see because
their eyes are protected by an additional transparent skin
the lodge has now seen
the arrival of the kids
between April and June the female will give birth
to one to four kids with hair and their eyes open
the young spend the first month in
the living quarters of the lodge
for six to eight weeks they're subtle by the mother
as long as the kids are in the lodge they're safe
but out in the waters of the sava
terrifying predators are waiting
catfish can grow to 100 1/2 meters long
and weigh more than 50 kilograms
some have even been known to grow to three
metres in length and reach weights of
over a hundred and fifty kilogram
the sava wetlands are home to one of the
largest catfish populations in Europe
they're usually loners
but in spring there are
sometimes unusual gatherings
the focus is usually a group of overweight
females with swollen bellies full of spawn
a large female can lay up
to half a million tiny eggs
and yet these whirling catfish are not mating this
puzzling spectacle is perhaps a kind of foreplay
the mating act takes place only between
two catfish in private after the male
has created a spawning burrow in the
shallow water close to the bank
among thick underwater vegetation
there are many suitable places along the
sava the quiet side arms are often
overgrown with a thick mat
of pond and water lilies
they're juicy branches are nourishing
tidbits for the Beavers
and the broad floating leaves are a welcome
diving board for France hunting insects
in this way the Fertile waters of the wetlands are a
good source of food for many species and a nursery
one of the most common fish in the
Sava is not even from this area
in the densely vegetated shoreline pumpkinseed fish with
their black mark on the gill cover have found a hole
at the end of the 19th century the fish was
introduced in Europe from North America
and escaped from some garden ponds since it
breeds several times a year it was able to spread
rapidly across the continent
the pumpkinseed protects its
spawning burrows aggressively
it will even attack very large intruders
one level higher another baby has
just freed itself of its eggshell
stripe iya squeakers or baby boars its
siblings already swimming around the nest
the chicks of the crested grebe do not all
hatch out at the same time but a day apart
surprisingly the parents offer
their babies freshly pulled feathers
even order the chicks eat them
one explanation might be this it's
possible that the feathers protect the
tender stomach linings of the babies
against sharp fish bones
the first weeks the chicks spend a lot
of time in a cozy hollow of warm down
this protects them against the cold
water and the hot Sun
frequently the parents will go swimming
with the chicks on their banks
and they have even been known to dive with
but this grebe is just looking for a
more comfortable position on the nest
in their piggy back position the chicks are relatively
safe from predators in the air and in the water
the sava wetlands offer many different
possibilities for undisturbed nesting
some build floating nests where
they can bring up their young
another crested species the hoop hole find safe
breeding in tree hollows in the oak forests
here the young wait for their parents who take turns to
bring food mainly crickets beetles and larger caterpillars
in the alluvial forests the penduline tit hangs its nest from
a branch to build the nest it uses fine vegetable fibers
sometimes even spider's webs
the soft pouches used to be collected
for use as children's slippers
the who posed nest is now
attracting unwanted attention
there are strange noises in the hollow
a Starling is intent on stealing nesting material
and the Hoopoe keeps well out of the way
discretion is the better part of valor
but what does the Starling really want it
flies off without the nesting material
so the Hooper parents can carry
on with feeding their young in peace
two-thirds of the landscape olio Nature
Reserve is covered with alluvial forests
one third is wet meadowland which provides the
storks with a well-stocked larder to choose from
every adults talk requires a pound of food a
day and the chicks need more than twice that
so store parents have to transport
several kilograms of food every day
they poke around in the grass to find insects
and mice amphibians slugs and earthworms
if the meadows are under water they
catch crayfish and small fish their
stalks are characteristic of the Nature Reserve
there are over 700 pairs breeding here
they're constantly
repairing their nests this means they
can grow over the years to 4 metres in
height and can weigh up to 600 kilograms
after over a month of incubation the
young storks have hatched
at the beginning one of the parents will
always stay with the nest provide shade and
regurgitate tidbits for the clamoring babies
everywhere in the wetlands
there are newborn babies
after a good five weeks of incubation
the mute swan cygnets have hatched
in their grayish white plumage
they're anything but ugly ducklings
they preen themselves in the water
hands together with their parents in the nest
the swans distribute oil from their
preen gland all over their plumage
to make every single feather waterproof
soon after hatching the cygnets are expected
to find their own food in the water
the parents were there longer necks may
be able to reach deeper into the water
but that doesn't mean they're going
to give away any of their lunch
the wetlands are fertile along the banks of
the snaking Sava river there are cormorants
the water is teeming with fish
the larger catfish have retreated to quieter regions
the younger catfish are swarming
in the open water like tadpoles
catching amphipods and insect larvae
this way they confuse fish predators that
have to be able to concentrate on one target
there are predators hiding
everywhere in the wetlands
like this spotted eagle
that's just grabbing a pumpkin seed fish
the noisy cormorant colony where the birds brood
together high in the trees can be heard from a distance
the older fledglings extract their lunches
from deep inside their parents throat pouch
if it's very hot the parents also give them water
the diverse bird life in the
wetlands can't be taken for granted
the fine balance can easily be disturbed
this can be seen from the
crappier doll side arm
where grey heron and
spoonbills breed side by side
the heron are frequently seen in
Europe and even nest in large towns
the more rare spoonbills however
only frequent intact wetlands
at the end of the 1980s this sidearm was
drained and the spoonbills disappeared
fortunately there are now 120 pairs
here reading beside the herons
after the sidearm was returned to its natural
state the spoonbills returned within two years
and are now bringing up their
young again in this joint colony
and even the young have a spoon shaped bill
today attends of all the spoonbills in
Europe breed in crappy Adal
this is why the bird with the strange shaped beak
was honored as the symbol of the Nature Reserve
in the slit of the sidearm there are
other birds with odd-looking beaks
the Bill of the pied Avocet
bends upwards towards the tip
while the spoon bill uses its extremely
sensitive bill to search the riverbed
for aquatic insects crayfish and clams
the Avocet sifts for small
animals in the shallow silt
even the young chicks emulate this
my swing their heads to detect prey
since their tools dictate the way
they search and what they find
they do not infringe on each other's
territory in the crocodile sidearms
we're into midsummer in the wetlands
and the entire beaver family
has taken to the water
the youngsters are still a little
apprehensive about the water
and have to be encouraged to swim or are
even carried by the bank an adult and a
juvenile from last year are combing
their fur using the special combing claw
on their hind feet and applying oil to
making waterproof
they tend to spend several hours a day in the
water on average and can't afford to catch cold
on average the sava wetlands are flooded
for 32 a hundred days a year
it's not only in spring but in any month of the year
that powerful rainfall can cause it to burst its banks
and generate fertile habitats for many creatures
including the Osprey although it only weighs one other
half kilos is able to catch fish weighing two kilograms
after locating them with its eagle eyes from afar
and picking them out of the water
in the sava wetlands with their
plentiful supplies of fish the Eagles also have
ideal locations for their IRA's in the tall trees
normally they produce two to three chicks
these youngsters are already a few weeks old
allowing both the parents
to leave the nest regularly
to bring home enough food
for the family
the labyrinthine waters of the wetlands
are often murky so not all the fish
hunters need to have such good eyes as
the Eagles that hum from high in the sky
the large catfish have relatively poor
eyesight but their whole body and in
particular their long feelers is
covered with sensitive sense organs
this allows them to notice quickly in
the muddy sediment of the sidearms
if a competitor has already
staked out a good hunting ground
with their large mouths catfish can
catch not only fish and crayfish
their hearing is so sensitive that they can detect vibrations
outside the water and go to check out the hunting options
in the flooded alluvial forests the catfish
is looking for a particular hunting ground
there are reports of small dogs ending
up inside the jaws of the catfish
this is where pigeons come
down to the water to drink
they're flapping wings are a giveaway
that attacked was a failure
the pigeons are wary and don't allow themselves
to be dragged into the water that easily
they're still thirsty though and come back
a new opportunity for the catfish
the pigeons are forewarned
for they keep coming back
the third attack is a success
in the summer The Meadows are a blaze of red
a sea of poppies growing in
a field near the village
in agriculture in the Sava wetlands
the emphasis is on livestock breeding
but in some places arable
farming is also possible
peppers and sweet corn cobs
dry outside the houses
as they have done for hundreds of years
there's twittering coming from the
rafters Housemartins
in the protected environment of old
houses we find a whole colony
some of the Housemartins have
been here twice this summer
the others still have
to complete their nests
they build the walls of their nests
from inside using moist lumps of earth
until there is only their front door left open
there's a plethora of building
materials in the Sarver wetlands
thanks to the moist surroundings these Martens can
always find lumps beside puddles and on the banks of the
waters even in the hottest summer
it takes around a fourth life to build a nest
and then they lay up to five eggs in it
and up in the loft there's
a lively commotion
the mouse eared bats spend the
daylight hours up here squeaking
most of these are females and they will give
birth to their young here and bring them up
hundreds sometimes even thousands
of bats vie for the best places
holding on tight with their claws
they spend the day hanging upside
down under the wooden roof
there will swarm out after darkness
falls and go searching for food
thanks to their large ears they can locate
their prey in the dark by ultrasound
mainly all manner of insects
in these moist weapons there are many
different midges and flies moths and beetles
the floodplains of the sava are of importance
to the protection of birds throughout Europe
on the one hand they're the breeding area for
over a hundred and forty different bird species
numerous waterfowl like the snipe nest
in these moist meadows
but for migrating birds to the sava wetlands are one
of the most important rest areas on the continent
here they can plan a stopover to
recover from their long flights
and eat to their heart's content
all-in-all no less than 240 bird species
have been registered in the Nature Reserve
including the curl you
where the syrup olia pigs plow up the
sava mud in spring we now get fresh grass
a great benefit to the
powerful paws of inna horses
with their broad hooves they have no
difficulty walking over the soften ground
in the summer they like to enjoy
a cooling bath in the sava
since the start of spring the horses have lived
here without any human influence in the wetlands
with their fluctuating water levels
this is the ideal environment
for grass snakes
that can hunt mainly toads and
amphibians in the moist surroundings
the snake could hardly catch
healthy fish in the river
but when the water recedes from the
flooded Meadows the fish left behind in
the puddles virtually leaps straight
into the grass snakes mouth
this easy to catch prey also attracts stalks
onto the moist meadows and pasture land
they pick the juiciest insects
often they will follow the cattle on horses because as they move
around grazing they dislodge grasshoppers and other creatures
the storks benefit from these free roaming
domesticated animals in many ways
if there were no horses or cattle
here there will be fewer storks
on the one hand puddles of this
kind are maintained by them
because horses and other livestock wallow
in them and keep the muddy areas open
the sava wetlands though a considerable degree of their
diversity to the hungry stomachs of these large herbivores
without the help of these
natural mowing machines
the damp pastures would soon
degenerate into closed oak forests
this traditional pasture farming keeps
the ancient cultural landscape alive
and encourages Himura files like the stork to
breed here in large numbers
by the end of the summer there are more
storks living in g-gosh than people
in many nests for chicks are
produced sometimes even 6
when it's really hot the parents will dribble water
from their beaks into those of the chicks
and eating grass snakes find their
way from the swamp to the nest
and from there into a storks stomach
in the late summer early morning miss
rise over the Nature Reserve
a melancholy idle
when the sava wetlands of Croatia remind us
of paintings by famous landscape artists
and that is no coincidence because large
regions of Europe used to look like this
before the rivers were forced to behave
and flooding was normal
times when all over the continent riparian
wetlands could only be used naturally for grazing
this created landscape diversity has
still seen in the landscape olia puddles
and pools on moist meadows
mocchi sidearms and river meanders
traditional woodland and pasture
while the paws Avena horses spend their winter in
their stables the pigs stay outside all year round
in the autumn they're driven into the
woods where they mainly eat acorns
these woodland pastures keep the
forests open and free of undergrowth
and that produces park-like landscapes in the wetlands
when autumn arrives there's a
lot of action to see and here
during the last warm days of the year the squirrels
and foxes build up their layers of winter fat
and in the country by the sava
the Red Deer are heard bellowing
those from the posavina region are
some of the strongest in Europe
the most important time of the year is
fast approaching the rutting season
attracted by the bellowing of the stags the
Hinds gather at the traditional meeting points
these are usually spaces
that have not grown over
the Stags need open spaces to give
them room to impress the Highlands
and intimidate their rivals
the last big wetland area in Europe
is still a coherent mix of river and
flooding managed pasture and diverse nature
it's like looking into the past of our continent
that shows us how natural flood protection
for large towns and cities can be
as in the sava wetlands of Croatia
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